Ultrasonic sensor for electronic sectorial scanning and echograph incorporating such a sensor

Abstract

Ultrasonic sensor and echograph with static sectorial scanning, especially for a wide angle picture, wherein according to a possible embodiment, the sensor comprises several groups of transducer elements forming between one another obtuse angles in such a way as to define overall a convex outline so that the delays or lags necessary to obtain a complete scanning be lower than with a conventional linear strip and thus easier to contol, the sensor being intended to be applied to medical echography.

I claim: 
     
       1. An ultrasonic sensor for electronic sectorial scanning, comprising: a plurality of groups of transducer elements formed into consecutive portions which are respectively aligned to present a convex outline to an object of scanning, each portion being distinguished from its adjacent portion by at least one of a discontinuity and a different radius of curvature. 
     
     
       2. Ultrasonic sensor according to claim 1, wherein it comprises two adjacent groups aligned according to a predetermined angle forming between one another. 
     
     
       3. Ultrasonic sensor according to claim 1, wherein it comprises at least three groups aligned according to consecutive straight line portions forming equal obtuse angles between one another. 
     
     
       4. Ultrasonic sensor according to claim 1, wherein it comprises a first group of transducer elements aligned as a straight line portion and second and third groups of transducer elements disposed as curved line portions, said second and third groups being situated symmetrically on both sides of said first group of elements. 
     
     
       5. An ultrasonic sensor as in claim 4 wherein said curved line portion defines an arc of a circle. 
     
     
       6. An ultrasonic sensor according to claim 1, wherein it comprises a first group of transducer elements disposed according to a curved line portion and second and third groups of transducer elements disposed according to straight line portions, said second and third groups being situated symmetrically on both sides of said first group. 
     
     
       7. An ultrasonic sensor according to claim 1, wherein the emitting faces of at least one group of aligned transducers according to a straight line portion are embedded in a layer of elastomeric material materializing a continuous convex external surface having a constant radius of curvature in the plane of the area to be visualized. 
     
     
       8. An ultrasonic sensor according to claim 1 further comprising sequencing means for independently controlling operations of each of said groups. 
     
     
       9. A sensor as in claim 8 wherein said sequencing means causes all of the transducer elements of a particular group to simultaneously operate. 
     
     
       10. A sensor as in claim 9 further comprising: means for receiving a signal from a transducer element;   delay means, coupled to said receiving means, for delaying said received signal in a plurality of discrete delay increments and for providing a plurality of discrete delay outputs; and   multiplexing means coupled to said plurality of discrete delayed outputs of said delaying means, for selecting one of said discrete delayed outputs of said delay means as an output of said multiplexing means.   
     
     
       11. An echograph comprising a sensor with electronic sectorial scanning comprising: a plurality of groups of transducer elements aligned to present a convex outline to an object to be scanned;   emitting-receiving means for organizing emitting-receiving sequences from at least one group of transducer elements, said emitting-receiving means comprising a number of emitting-receiving channels at least equal to the number of transducer elements of one of said groups; and   means for applying a predetermined delay between the transducer elements of said one group.   
     
     
       12. Echograph according to claim 11, wherein each group comprises the same number of transducer elements, wherein the said emitting-receiving means comprise a number of emitting-receiving channels equal to the number of transducer elements of each group and further comprising sequential switching means, intercalated between said groups and said emitting-receiving channels for cyclically and in a given order interconnecting the transducer elements of said groups and said emitting-receiving channels. 
     
     
       13. Echograph according to claim 11, wherein each group comprises the same number of transducer elements, wherein the said emitting-receiving means comprises a number of emitting-receiving channels equal to the total number of transducer elements of all of the groups combined, and further comprising control means for said channels, disposed so as to provoke substantially and simultaneously an emitting-receiving sequence in each group. 
     
     
       14. Echograph according to claim 11, wherein the sensor comprises a central group of transducer elements, and two lateral groups on both sides of the central group, each said lateral group comprising a number of transducer elements equal to half the number of transducer elements of said central group, wherein the said emitting-receiving means comprises a number of emitting-receiving channels equal to the number of transducer elements of the central group, and further comprising sequential switching means, intercalated between said groups and said emitting-receiving channels for one by one and cyclically interconnecting said channels with said transducer elements of said central group and then with said transducer elements of the lateral groups. 
     
     
       15. An ultrasonic sensor according to claim 11 wherein said emitting-receiving means independently controls each of said groups. 
     
     
       16. A sensor as in claim 15 wherein said emitting-receiving means causes all of the transducer elements of a particular group to simultaneously operate. 
     
     
       17. A sensor as in claim 15 wherein said delaying means delays said signal in a plurality of discrete delay increments and provides a plurality of discrete delay outputs; and further compromising   multiplexing means coupled to said plurality of discrete delayed outputs of said delaying means, for selecting one of said discrete delayed outputs of said delay means as an output of said multiplexing means.